1. Field of the Invention
Embodiments of the invention described herein pertain to the field of medical and nutritional compositions. More particularly, but not by way of limitation, one or more embodiments of the invention comprises methods and pomegranate compositions for treatment of urinary tract infections.
2. Description of the Related Art
Urinary tract infections (UTIs) are a widespread problem. Considerable morbidity, multiple antibiotic treatments, and costs result from its common recurrence. Regretfully, uropathogenic Escherichia coli (UPEC), the major pathogen involved in these infections, has become increasingly resistant to β-lactams and fluoroquinolones. Evidence has suggested that consumption of cranberries (Vaccinium macrocarpon Ait.) and cranberry juice can be used to help prevent UTI. Consumption of cranberry may prevent adhesion of E. coli strains to the uroepithelium thus interfering with this a critical first step in the infection process. Of note, cranberry's effect can be seen with multidrug resistant bacterial strains as well. Data suggests that cranberry's proanthocyanidins (PACs), specifically the unusually condensed tannins with A-type linkages, inhibit E. coli (primarily P-fimbriated) adhesion to uroepithelial cells in vitro (Liu Y et al.: Role of cranberry juice on molecular-scale surface characteristics and adhesion behavior of Escherichia coli. Biotechnol Bioeng 2006, 93:297.305; Howell A B, et al.: Inhibition of adherence of Pfimbriated Escherichia coli to uroepithelial-cell surfaces by proanthocyanidin extracts from cranberries. N Engl J Med 1998, 339:1085.1086; Foo L Y et al.: A-type proanthocyanidin trimers from cranberry that inhibit adherence of uropathogenic P-fimbriated Escherichia coli. J Nat Prod 2000, 63:1225.1228; Gupta K et al.: Cranberry products inhibit adherence of uropathogenic Escherichia coli to primary cultured bladder and vaginal epithelial cells. J Urol 2007, 177:2357.2360), and ex vivo (Howell A B et al.: In vivo evidence that cranberry proanthocyanidins inhibit adherence of P-fimbriated E. coli bacteria to uroepithelial cells. FASEB J 2001, 15: A284; Howell A B, et al.: Dosage effect on uropathogenic Escherichia coli anti-adhesion activity (“AAA”) in urine following consumption of cranberry powder standardized for proanthocyanidin content: a multicentric randomized double blind study. BMC Infect Dis 2010, 10:94.
Anecdotal evidence suggests that consumption of pomegranates may be beneficial for urinary tract health. Pomegranates contain hydrolyzable tannins which have been shown to have a number of health promoting properties. The role of pomegranate extracts as anti-microbial compounds has also been explored (Chulasiri, M. et al. 1995. Mahidol. Iniv. J. Pharm. Sci. 22:1-159; 25. Chulasiri, M. 1997. Thai. J. Phytopharm. 4:25-30; 26. Stewart, G. S. et al. 1998. J. Appl. Microbiol. 84:777-783; Segura, J. J. et al. 1990. Arch. Invest. Med. 21:235-239). However, in each case, the pomegranate extract was shown only to inhibit bacterial growth, not to inhibit bacterial adherence to surfaces.
U.S. patent application Ser. No. 10/332,425 discloses hydrolyzable tannin extracts from plants which acts to prevent bacterial adherence to surfaces. Hydrolyzable tannin extracts from plants, in particular pomegranate and persimmon, were shown to have activity to inhibit adhesion of bacteria to surfaces.